Making use of a relation proposed by Wielen (1977), a new empirical relation between Call emission flux and stellar age is derived by analyzing Wilson and Woolley's spectroscopic data (1970) of late type main sequence stars (K0-M5) and kinematic properties of those stars given by Gliese (1969). The proposed relation shows that the emission flux excess of the Call H-K lines, F ′ k + F ′ k introduced by Linsky et al. (1979) decreases with stellar age τ as τ − 0.51 , consistent with the inverse square law as noted by Skumanich (1972).

ABSTRACT
Ⅰ. INTRODUCTION
Ⅱ. ANALYSIS OF WILSON AND WOOLLEY’S CaⅡ OBSERVATIONS
Ⅲ. SPACE VELOCITY DISTRIBUTIONS OF WILSON AND WOOLLEY’S STARS AND AGE DETERMINATION
Ⅳ. RELATION BETWEEN CaⅡ EMISSION FLUX EXCESS AND STELLAR AGE
Ⅴ. A BRIEF SUMMARY AND CONCLUSIONS
REFERENCES

• PARK YOUNG DEUK(Department of Astronomy, Seoul National University)
• YUN HONG SIK(Department of Astronomy, Seoul National University)